[SRU][Zesty][PATCH 0/1] KVM: PPC: Book3S HV: Enable TM before accessing TM registers

Joseph Salisbury joseph.salisbury at canonical.com
Fri Aug 18 20:40:55 UTC 2017


BugLink: http://bugs.launchpad.net/bugs/1709784

== SRU Justification ==
KVM on 16.04.3 throws an error.  This is a regressino due to commit 46a704f8409f.

Commit 46a704f8409f ("KVM: PPC: Book3S HV: Preserve userspace HTM state
properly", 2017-06-15) added code to read transactional memory (TM) registers
but forgot to enable TM before doing so.

This commit fixes this regressoin and landed in mailine as of v4.13-rc3  It has been cc'd to upstream
stable.  However, it has not landed in stable yet.  It is also needed in Xenial, but
 will be sent in another SRU to X due to context diffs between the patches.

== Fix ==
commit e47057151422a67ce08747176fa21cb3b526a2c9
Author: Paul Mackerras <paulus at ozlabs.org>
Date:   Fri Jul 21 13:57:14 2017 +1000

    KVM: PPC: Book3S HV: Enable TM before accessing TM registers


== Regression Potential ==
Low since it is only enabling TM so we can read the TM SPRs.

== Test Case ==
A test kernel was built with this patch and tested by the original bug reporter.
The bug reporter states the test kernel resolved the bug.



Paul Mackerras (1):
  KVM: PPC: Book3S HV: Enable TM before accessing TM registers

 arch/powerpc/kvm/book3s_hv.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

-- 
2.7.4





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